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1.
Human papilloma virus (HPV) infection is the main etiological factor for cervical intraepithelial lesions (CIN). An important characteristic of this process is the loss of genome stability. Therefore, it is imperative to use biomarkers of DNA damage caused by genomic instability to identify high risk individuals. We investigated the frequency of micronuclei (MN) in peripheral blood lymphocytes (PBL) of 20 patients, diagnosed as histologically CIN 1 and 10 healthy controls. We also examined the frequency of other nuclear anomalies including nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) in PBL of patients with CIN 1 and healthy controls, and evaluated the benefits of p16INK4a and Ki-67 (p16INK4a/Ki-67) immunohistochemical double staining for identifying cervical squamous cells that express HPV E6/E7 oncogenes. We analyzed the association between the frequency of MN in PBL and the amount of p16INK4a/Ki-67 co-expression in CIN 1 patients to establish genomic instability. Among CIN 1 subjects, 15% exhibited diffuse p16INK4a/Ki-67 co-expression and were considered high positive, 25% of the CIN 1 cases exhibited p16INK4a/Ki-67 co-expression restricted to the lower part of the epithelium and were considered low positive and the remaining 60% of cases were negative. The frequency of MN, NPBs and NBUDs differed significantly among groups. We found a statistically significant positive correlation between p16INK4a/Ki-67 co-expression and the frequency of MN, NPBs and NBUDs in PBL. Our findings demonstrate the efficacy of p16INK4a/Ki-67 double immunostaining for histological samples with CIN 1. MN frequency in PBL might be useful for detecting genomic instability in cases of HPV infection and CIN.  相似文献   
2.
Osmotically inactive skin Na(+) storage is characterized by Na(+) accumulation without water accumulation in the skin. Negatively charged glycosaminoglycans (GAGs) may be important in skin Na(+) storage. We investigated changes in skin GAG content and key enzymes of GAG chain polymerization during osmotically inactive skin Na(+) storage. Female Sprague-Dawley rats were fed a 0.1% or 8% NaCl diet for 8 wk. Skin GAG content was measured by Western blot analysis. mRNA content of key dermatan sulfate polymerization enzymes was measured by real-time PCR. The Na(+) concentration in skin was determined by dry ashing. Skin Na(+) concentration during osmotically inactive Na(+) storage was 180-190 mmol/l. Increasing skin Na(+) coincided with increasing GAG content in cartilage and skin. Dietary NaCl loading coincided with increased chondroitin synthase mRNA content in the skin, whereas xylosyl transferase, biglycan, and decorin content were unchanged. We conclude that osmotically inactive skin Na(+) storage is an active process characterized by an increased GAG content in the reservoir tissue. Inhibition or disinhibition of GAG chain polymerization may regulate osmotically inactive Na(+) storage.  相似文献   
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4.
The effect of diethyl pyrocarbonate on chromatophores and isolated pigment--protein complexes of Chromatium minutissimum was studied. It is shown that modification of histidine residues results in the destruction of the core antenna LHI (B880) and in a spectral shift from 850 to 830 nm in the peripheral antenna LHII (B800-850). In the purple sulfur bacterium Chromatium minutissimum the pigment--protein complexes B800-B850 (peripheral antenna, LHII) and B880 (core antenna, LHI) collect and transmit the absorbed light energy to the reaction centers. The composition of pigments and proteins as well as primary structure of the majority of polypeptides in both types of complexes from various photosynthetic bacteria have been determined.  相似文献   
5.

Objective

Na+ can be stored in muscle and skin without commensurate water accumulation. The aim of this study was to assess Na+ and H2O in muscle and skin with MRI in acute heart failure patients before and after diuretic treatment and in a healthy cohort.

Methods

Nine patients (mean age 78 years; range 58–87) and nine age and gender-matched controls were studied. They underwent 23Na/1H-MRI at the calf with a custom-made knee coil. Patients were studied before and after diuretic therapy. 23Na-MRI gray-scale measurements of Na+-phantoms served to quantify Na+-concentrations. A fat-suppressed inversion recovery sequence was used to quantify H2O content.

Results

Plasma Na+-levels did not change during therapy. Mean Na+-concentrations in muscle and skin decreased after furosemide therapy (before therapy: 30.7±6.4 and 43.5±14.5 mmol/L; after therapy: 24.2±6.1 and 32.2±12.0 mmol/L; p˂0.05 and p˂0.01). Water content measurements did not differ significantly before and after furosemide therapy in muscle (p = 0.17) and only tended to be reduced in skin (p = 0.06). Na+-concentrations in calf muscle and skin of patients before and after diuretic therapy were significantly higher than in healthy subjects (18.3±2.5 and 21.1±2.3 mmol/L).

Conclusions

23Na-MRI shows accumulation of Na+ in muscle and skin in patients with acute heart failure. Diuretic treatment can mobilize this Na+-deposition; however, contrary to expectations, water and Na+-mobilization are poorly correlated.  相似文献   
6.
Malaria is still a major public health problem in Brazil, with approximately 306 000 registered cases in 2009, but it is estimated that in the early 1940s, around six million cases of malaria occurred each year. As a result of the fight against the disease, the number of malaria cases decreased over the years and the smallest numbers of cases to-date were recorded in the 1960s. From the mid-1960s onwards, Brazil underwent a rapid and disorganized settlement process in the Amazon and this migratory movement led to a progressive increase in the number of reported cases. Although the main mosquito vector (Anopheles darlingi) is present in about 80% of the country, currently the incidence of malaria in Brazil is almost exclusively (99,8% of the cases) restricted to the region of the Amazon Basin, where a number of combined factors favors disease transmission and impair the use of standard control procedures. Plasmodium vivax accounts for 83,7% of registered cases, while Plasmodium falciparum is responsible for 16,3% and Plasmodium malariae is seldom observed. Although vivax malaria is thought to cause little mortality, compared to falciparum malaria, it accounts for much of the morbidity and for huge burdens on the prosperity of endemic communities. However, in the last few years a pattern of unusual clinical complications with fatal cases associated with P. vivax have been reported in Brazil and this is a matter of concern for Brazilian malariologists. In addition, the emergence of P. vivax strains resistant to chloroquine in some reports needs to be further investigated. In contrast, asymptomatic infection by P. falciparum and P. vivax has been detected in epidemiological studies in the states of Rondonia and Amazonas, indicating probably a pattern of clinical immunity in both autochthonous and migrant populations. Seropidemiological studies investigating the type of immune responses elicited in naturally-exposed populations to several malaria vaccine candidates in Brazilian populations have also been providing important information on whether immune responses specific to these antigens are generated in natural infections and their immunogenic potential as vaccine candidates. The present difficulties in reducing economic and social risk factors that determine the incidence of malaria in the Amazon Region render impracticable its elimination in the region. As a result, a malaria-integrated control effort - as a joint action on the part of the government and the population - directed towards the elimination or reduction of the risks of death or illness, is the direction adopted by the Brazilian government in the fight against the disease.  相似文献   
7.
Male Rocky Mountain elk (Cervus elaphus nelsoni) produce loud and high fundamental frequency bugles during the mating season, in contrast to the male European Red Deer (Cervus elaphus scoticus) who produces loud and low fundamental frequency roaring calls. A critical step in understanding vocal communication is to relate sound complexity to anatomy and physiology in a causal manner. Experimentation at the sound source, often difficult in vivo in mammals, is simulated here by a finite element model of the larynx and a wave propagation model of the vocal tract, both based on the morphology and biomechanics of the elk. The model can produce a wide range of fundamental frequencies. Low fundamental frequencies require low vocal fold strain, but large lung pressure and large glottal flow if sound intensity level is to exceed 70 dB at 10 m distance. A high-frequency bugle requires both large muscular effort (to strain the vocal ligament) and high lung pressure (to overcome phonation threshold pressure), but at least 10 dB more intensity level can be achieved. Glottal efficiency, the ration of radiated sound power to aerodynamic power at the glottis, is higher in elk, suggesting an advantage of high-pitched signaling. This advantage is based on two aspects; first, the lower airflow required for aerodynamic power and, second, an acoustic radiation advantage at higher frequencies. Both signal types are used by the respective males during the mating season and probably serve as honest signals. The two signal types relate differently to physical qualities of the sender. The low-frequency sound (Red Deer call) relates to overall body size via a strong relationship between acoustic parameters and the size of vocal organs and body size. The high-frequency bugle may signal muscular strength and endurance, via a ‘vocalizing at the edge’ mechanism, for which efficiency is critical.  相似文献   
8.
Klemuk SA  Riede T  Walsh EJ  Titze IR 《PloS one》2011,6(11):e27029
Vocal production requires active control of the respiratory system, larynx and vocal tract. Vocal sounds in mammals are produced by flow-induced vocal fold oscillation, which requires vocal fold tissue that can sustain the mechanical stress during phonation. Our understanding of the relationship between morphology and vocal function of vocal folds is very limited. Here we tested the hypothesis that vocal fold morphology and viscoelastic properties allow a prediction of fundamental frequency range of sounds that can be produced, and minimal lung pressure necessary to initiate phonation. We tested the hypothesis in lions and tigers who are well-known for producing low frequency and very loud roaring sounds that expose vocal folds to large stresses. In histological sections, we found that the Panthera vocal fold lamina propria consists of a lateral region with adipocytes embedded in a network of collagen and elastin fibers and hyaluronan. There is also a medial region that contains only fibrous proteins and hyaluronan but no fat cells. Young's moduli range between 10 and 2000 kPa for strains up to 60%. Shear moduli ranged between 0.1 and 2 kPa and differed between layers. Biomechanical and morphological data were used to make predictions of fundamental frequency and subglottal pressure ranges. Such predictions agreed well with measurements from natural phonation and phonation of excised larynges, respectively. We assume that fat shapes Panthera vocal folds into an advantageous geometry for phonation and it protects vocal folds. Its primary function is probably not to increase vocal fold mass as suggested previously. The large square-shaped Panthera vocal fold eases phonation onset and thereby extends the dynamic range of the voice.  相似文献   
9.
10.
Based on corresponding ascocarp ontogeny and thallus structure, the genera Euopsis and Harpidium are included in the family Lichinaceae. In the two species of Euopsis, E. granatina and E. pulvinata, the apothecia develop from ascogonia in generative tissue, while in H. rutilans they are pycnoascocarps. In thallus anatomy, the species of Euopsis resemble Pyrenopsis haematopsis and allied species, while H. rutilans corresponds in structure and development of the thallus and apothecia to Pyrenopsis haemaleella (syn. P. sphinctotricha). H. rutilans is the first member of Lichinaceae known to have only a green algal symbiont. In E. granatina, two phycobionts are always present, a species of Gloeocapsa and a chlorococcalean alga. In Euopsis and Harpidium, the ascus wall is composed of an outer, non-expansible and an inner, expansible layer; the latter surrounds the protoplast as an amyloid collar, which expands during spore release into a long, tapering rostrum. In Euopsis, the outer wall layer is strongly amyloid and the upper part separated from the expanded amyloid rostrum by a non-amyloid zone, appearing like a slit in LM studies. The ultrastructure and function of the ascus in E. granatina has been studied in TEM and is interpreted as functionally unitunicate-rostrate. Unitunicate asci with short rostrum are described for P. haemaleella and P. haematopsis.  相似文献   
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